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thats a nice and also clever application to get some droop back in there.
yeah the 6cup was using 240/260 from the factory but not many people kept those on long. its pretty rough going if you arent on somewhere nice and smooth.
i want to ask you ref the rake but i'll PM rather than take this thread on a tangent.

va122

What is that in pounds? Can't figure out the conversion.

911SLOW

1 N/mm = 5.7 lbs/in

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approx 1370lbs front and 1485lbs rear for the mains, 246lbs front and 285lbs for the helpers.
as 911slow said, the 997 uses 1485lbs front and rear as delivered.
i believe the euro 6GT3RS used 228lbs front and 514lbs rear( rear was progressive so this was its max value) as delivered just to give you something as a comparo.

va122

Holy Crap! I thought I had too much spring!

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hahahaha. that about made me spray coffee all over my laptop. too funny.
and this with an 1150kg dry weight.

911SLOW

one can never have too much spring



Since we r talking gt3 and springs here is the results of a research I did after receiving some money of course for the 7GT3 forum. : )

FRONT:

996.1 GT3
PART NUMBER: 996 343 531 91
SPRING RATE: 35N/mm

996.2 GT3
PART NUMBER: 996 343 531 95
SPRING RATE: 40N/mm

996.2 GT3 RS
PART NUMBER: 996 343 531 97
SPRING RATE: 45N/mM

997.1 GT3
PART NUMBER: 996 343 531 95
SPRING RATE: 40N/mm

997.2 GT3
PART NUMBER: 997 343 531 94
SPRING RATE: 49N/mm



REAR:

996.1 GT3
PART NUMBER: 996 333 531 91
SPRING RATE: 65N/mm

996.2 GT3
PART NUMBER: 996 333 531 95
SPRING RATE: 95N/mm

996.2 GT3 RS
PART NUMBER: 996 333 531 95
SPRING RATE: 95N/mm

997.1 GT3
PART NUMBER: 997 333 531 93
SPRING RATE: 105N/mm

997.2 GT3
PART NUMBER: 997 333 531 95
SPRING RATE: 115N/mm

997CUP
Fmain length mm - N/mm: 100-260 997.343.531.90
Ftender length mm - N/mm : 75–43 996.343.537.90

Rmain length mm - N/mm: 130-260 996.333.531.90
Rtender length mm - N/mm: 60-50 996.333.537.90

John

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thanks for the info. i had been told 40Nmm for the RS front. bad info so i'll make a note.
my cup service book shows 40Nmm for the rear helper spring on the 7cup though and not 50. i checked the earlier 7cup service manual and its the same for this too.

911SLOW

No it's 50

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hmm indeed parts page does say that..... but go to the suspension info page for the 2006 or 2008 cup (page 15) where it details it all and it clearly says 40 for rear axle helper spring for both cars. who knows. when im next at mine ill look and see if it says on it.
im too much of a technophobe to host a page print to let you see

tbh the majority of stuff those books say is mostly hogwash anyways just as the bulk of the "R" part numbers always end up with you getting a road car part delivered but paying a different price. i assume its meant as a "guide"

996FLT6

So when u revalve the shocks what are the specs of the revalving? Mike

himself

Back to regularly scheduled programming:

Below are the spring specs I am planning on using. Will this setup work? Am I going to have headaches setting it up. And what kind of ride height will I probably end up at?

[Length-dia-N/mm [(inches)/(ft/lbs)]
Main
160-60-140 (6.29 in)/(798)
120-60-110 (4.7 in)/(627) (4.7)

Tenders
60-60-25 (2.36)/(143)
60-60-45 (2.36)/(257)

Also, does anyone have the actual part numbers of what I need to get the rears to fit? [Perches, monoball, spring hat?] Perhaps even a ball park for prices?

-td

911SLOW

A helper spring is used to keep the main spring tight between the perches when the suspension is at full droop. So has a very soft rate, on the order of let’s say 2N/mm. It's just strong enough to push the main spring up against the upper spring perch, but that's about it.
If you are using a helper spring when compressed you have to accommodate its compressed thickness as a spacer lets say less than half an inch tall to calculate were the height might be in conjunction with the chosen height of the main spring. And actually your suspension will have linear springs.

In your case with the numbers you mention and by using a tender spring instead of a helper spring that has a rate in the region of 20 to 50 N/mm together with a 120-160N/mm main spring together yield a progressive overall spring rate.
The tender spring may not be fully compressed at static ride height but will quickly become so as the suspension goes into bump. This will give a better ride in slow bumpy roads.
A tender spring as is made from thicker wire does not compress quite as flat but around 2 inches. Also depending on the rate of the tender spring and the car weight or forces applied the main spring may partially compress before the tender spring is compressed flat.
It is quite tricky to give what numbers will work exactly and that has to do with personal preferences diving style, tyres used and track surface. Also the dampers should be able to match the spring rates.
The ride height is a combination of height target you have and required droop level.
Too many variables. Maybe you should consult someone that has the same dampers and ask what they are using and with what results or better have access to a couple of tender and main springs to experiment.

911SLOW

pm your email I have a list of HR with prices and block lengths spring travels and loads maybe it will help you.

va122

I always thought helper and tender were the same thing! WTF do I have?